<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style type="text/css">
      div {
        border: 2px solid cadetblue;
      }
      #div{
        color: cadetblue;
      }
      .span{
        color: #b3d4fc;
      }
    </style>
</head>
<body>
    <!--需求1：分别定义两个 div、span标签，分别修改每个 div 标签的样式为：边框1个像素，实线，红色。-->
    <div id = "div">div标签1</div>
    <div>div标签2</div>
    <span class="span">span标签1</span>
    <span>span标签2</span>
</body>
</html>
